Industrial articulated robot linear interpolation control device

In a control device for an industrial articulated robot which operates according to a teaching playback method, in which linear interpolation between two predetermined points is carried out, and dividing means are provided to divide a distance between said two points into segments which are determined by a command velocity, an interpolation time interval and the distance between said two points, said device having means for determining interpolation increments of motion along articulation drive axes, said interpolation increments corresponding to said segments, the improvement comprising:

• first means for changing the number of segments for every interpolation time interval so that, when a wrist axis speed is smaller than a speed corresponding to a maximum speed of revolution of a drive electric motor of said wrist axis, the orientation of said wrist is controlled to move at a uniform speed between said two points, and so that when said wrist axis speed exceeds the speed corresponding to the maximum speed of revolution of said drive electric motor, a second means changes the number of segments for every interpolation time interval so that the rate of movement in posture of said wrist does not exceed the speed corresponding to the maximum speed of revolution of said drive electric motor.